It was a race unlike any that Southborough native and marathoner Barrett Wilson-Murphy had ever entered, featuring a Delta Air Lines flight attendant, a generous stranger, a very special yellow-and-blue shirt, and a mad dash to the finish by his own mother.

Wilson-Murphy, a Boston College Law School student, has been studying this semester in London. A four-time Boston Marathoner, he will be one of the runners in Sunday’s London Marathon.

After Monday’s bombings, Wilson-Murphy thought there would be no better way for him to show his support for those back home than by wearing an official 2013 Boston Marathon runner’s shirt in the London race. But where could he find one and how could it get to him in time?

Adidas, the official clothing provider for the Boston Athletic Association, provides shirts only to registered runners, and those reselling shirts on eBay couldn’t guarantee delivery by race time. Wilson-Murphy needed someone to donate a running shirt, and fast.

Back in Boston his sister, Molly, spread the word through friends and Facebook until she found Ian Nurse, a friend of a friend who was one of the top 50 finishers in Monday’s Marathon. She picked up Nurse’s shirt at his Beacon Hill apartment Wednesday night, but every delivery service — Fed­Ex, DHL, UPS, and the US Postal Service — told her it wouldn’t arrive in London until Monday, which would be too late.

Virgin airlines, which sponsors the London Marathon, tried to help but couldn’t promise the shirt would make it directly into Wilson-Murphy’s hands. So Karen Dillon, a family friend and retired Delta Air Lines flight attendant, asked her former co-workers if anyone was flying from Boston to London this weekend.

If Hurley’s flight was delayed, would she be reassigned to another flight? Worse, because of the upheaval, Hurley still hadn’t received the shirt as of midafternoon Friday.

That’s when Wilson-Murphy’s mother, Cindy Wilson of Canton, entered the race, dashing with the shirt to meet Hurley at the Framingham Logan Express. But Hurley was nowhere to be found.

“She was in a different parking lot,” Molly Wilson-Murphy said, “so my mom ran through red lights to get to her 10 minutes before her bus left for Logan.”

In London, Barrett Wilson-Murphy remained glued to his computer to see if the flight would land as scheduled, which it did. At 10:30 a.m. Saturday London time he crossed the city to reach the flight attendant’s hotel.

Hurley was asleep but had left the shirt for him at the front desk. His mother had placed it in a colorful gift bag with a note that read, “Good Luck.”

When the starting gun sounds in Greenwich Park on Sunday, Wilson-Murphy will be wearing the shirt, along with his own Boston Marathon hat and a black ribbon that every runner in London’s race has been given to wear in honor of those killed or injured Monday.

“I think it’s just going to be a very emotional moment for me,” Wilson-Murphy said.

After the race for the shirt, running 26.2 miles might actually be the easy part.